Hepatitis C (HCV) is the most common chronic blood infection in the US, and the leading cause of chronic liver disease. HCV treatments that can cure the virus are available and dramatically improving. Quite recently, new and important evidence-based policies for HCV testing in primary care have been disseminated. Guidelines from the CDC and the USPSTF acknowledging challenges and possible inaccuracies in past risk-assessment approaches to HCV screening, and noting much higher HCV prevalence in those born between 1945-1965 now recommend 1-time universal HCV testing in the birth cohort between 1945-1965 (birth-cohort testing). Under new guidelines, clinician assessment of HCV risk factors (IVDU, multiple sex partners, incarceration, etc) followed by HCV test if indicated is still the strategy of choice for those not in the birth-cohort. VA national data describing facility rates of birth-cohort Veterans ever having been HCV tested range from some with gratifyingly high rates (max of 91%) but many facilities with substantial room for improvement (min of 34%). Therefore birth-cohort HCV testing within VA has many potential benefits, but implementation issues remain in order to optimally shape policy. Attitudes (barriers and facilitators) of clinicians and primary care teams toward a birth-cohort HCV testing approach are unknown. Furthermore, Veterans differ from the general US population - younger, OEF/OIF Veterans returning from deployment may be at substantially higher HCV risk. Strategies for repeat testing in those at ongoing risk may be necessary, and might need to be a parallel priority to a VA birth-cohort initiative. Understanding particular issues facing high risk Veterans, and adapting strategies for non-birth-cohort Veterans will likely be important. In an RRP research proposal we will: 1. Assess primary care providers' knowledge, attitudes, and beliefs about HCV testing and treatment, and about clinical, organizational, and contextual barriers and facilitators to VHA HCV testing program implementation. 2. Draft a primary care HCV testing program adapted from our recent HIV and non-VA HCV testing research, and collect provider responses, critiques, suggestions and adaptations. This study will be an essential component of HHQUERI's strategy for exporting lessons-learned from our past experience with implementing HIV testing to the new challenges of HCV. It will be an essential part of Goal 1 of the HHQUERI Strategic Plan - Better Disease Identification. The findings will complement experience and results from the team's previous AHRQ-funded research outside VA, of HCV risk assessment and birth cohort testing in primary care (Drainoni, Gifford), as well as from lessons learned from the HHQUERI's regional and national HIV testing implementation research projects and the VISN1-wide HIV testing dissemination project, to develop a model, and plan for implementation. Still, many evidence-based recommendations, while robust, are not put into practice - in part because there is limited buy-in from those responsible for implementing the practice. Without knowledge of what providers and patients view as barriers and facilitators to testing, developing a successful implementation model will not be possible. Study results will contribute to understanding of the HHQ Integrated Implementation model, a novel synthesis of the Rogers Diffusion and the PARiHS Implementation models. This new model includes important elements such as organizational and policy factors necessary to adopt new recommendations. Because of the recent change in national HCV antibody testing guidelines and need for optimal data to guide VA policy about whether and how to adopt these guidelines, this project is among the very top priorities of the VA Office of Public Health - Public Health Pathogens Program.